Draw: nudge by grid division

How do you nudge with arrow keys by exactly one grid division in libreoffice draw? Right now I have the grid set to 0.5" with 10 sub-divisions. Dragging with the mouse cursor snaps to all 10 positions correctly. However, nudging with the arrow keys appears to be completely disconnected from the grid - nudging moves objects by somewhere between 1/12 and 1/13 of a major grid, and totally screws everything up as nothing is aligned to the grid after nudging. Where is the setting to fix this? Or should I be opening a bug report?

Aside from the fact there are still a lot of people stuck with the inch system, there is no way that I can see to grab a window of objects and drag them on grid lines, so shifting a drawing that needs accuracy requires moving each object one at a time. Shifting an object by one pixel may be useful, but tying Shift and Alt to the major and minor grid only makes common sense. Seriously, it's not practical to use our calculators to figure out how to nudge an object by one grid division.